LLY Truck Crank Signal Issue - P0335

Shane H

New member
Jul 23, 2024
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Alberta, Canada
Ran the truck in my sig dry about 100m away from the fuel station. Was able to get it pushed close enough. Got it to run for 5 minutes but still had to haul it home that night.
Bled the return lines, bled the banjo fitting on the top side of the FICM. Bled the schrader valve by the alternator. Even bled a few of the accessible injectors. and both rails. Truck has a FASS 165. Filters are primed. Truck will NOT fire on diesel. I pinched the return line. Disconnected the FCA. Truck throws an intermittent P0335.

Edit* After much messing around, determined I did not run truck out of fuel. Ended up being a crank signal/rpm signal issue.
 
Last edited:

kidturbo

Piston Tester
Jul 21, 2010
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Somewhere On The Ohio
www.marinemods.us
Sounds like it might have stuck the FP regulator. The P0335 is weird because it won't fire without the cam signal, but that's no ways related to running out of fuel. Need to verify you have decent fuel pressure on the rail for it to fire, and make sure you are getting RPM signal. Last look at that cam sensor missed pulse data and see if maybe it is a bad connection.
 

Shane H

New member
Jul 23, 2024
5
0
1
Alberta, Canada
I'll verify everything else next week when I get time to look at it again. Fuel Rail Pressure climbs to 27k psi as I'm cranking the starter and dwindles back down to nothing when leaving the key on accessory. Desired Fuel Pressure is asking for 5800-6k at start up. This is the same with the FCA plugged in and unplugged.
 

Shane H

New member
Jul 23, 2024
5
0
1
Alberta, Canada
If it's making good cranking pressure, then most certainly it's electrical.

Sent from my SM-S901U using Tapatalk
Yep. Loaded up the parts cannon. Had the batteries warrantied as they were only generating half the CCA and threw a crank position sensor at it. Still P0335. And Ive verified that I dont have RPM signal.
 

JoshH

Daggum farm truck
Staff member
Vendor/Sponsor
Feb 14, 2007
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Texas!!!
You need to be looking into that CKP code. Here's the diagnostics for it if you need some guidance on figuring it out.
 

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Ron Nielson

Active member
Oct 11, 2009
765
144
43
Berryton, KS
Fuel Rail Pressure climbs to 27k psi as I'm cranking the starter ...... This is the same with the FCA plugged in and unplugged.
Yup, anytime the FPR is not powered for any reason, you get full fuel pressure. There is definitely a problem in the FPR or wiring somewhere.